The city of Abu Dhabi is growing every year in population, urban extent and energy demand. This research focuses on the application of two simulation programs to estimate changes in urban climate associated with continued development in Abu Dhabi: The Urban Weather Generator (UWG) and ENVI-met. Simulation with these two software packages are validated with the site data measured in downtown Abu Dhabi. A comparison analysis (in the different seasons) between the rural data, the simulation output, and the site measurements shows the variations of the UHI in this Middle Eastern city and the potential of the validated tools. The main aims of this study are: (a) to make a seasonal validation of the UWG for the city of Abu Dhabi (referring to urban-rural available data). The tool was previously validated for a year (no seasonal division) for Abu Dhabi, Toulouse, Basel, Singapore, Rome and Barcelona. The simulations are based on the 2016 version of the Urban Weather Generator. The analysis is separated into three main seasons (instead of the full year): winter, spring, summer. (b) To make a seasonal validation and improve the second tool evaluated in this study, ENVI-met 4.0. The software can simulate urban temperature, humidity and wind speed. Guides are proposed for the enhancement of the accuracy of both estimation procedures. Referring to the results, UWG tends to overestimate the canyon temperature during the summer and has a more realistic estimation on the winter season. ENVI-met has better estimations of temperatures during the summer season compared to UWG. Finally, the UWG weather file contributes a more detailed energy model on a mesoscale model. It considers the seasonal effect and shows the impact of the climate on profiling the UHI phenomena. ENVI-met needs improvement in calculating the anthropogenic heat and in calculation of the mean radiant temperature. Sustainability 2019, 11, 4378 2 of 20districts. The latest study shows that the release of the anthropogenic heat creates an unstable layer in the lower level of the atmosphere-even during the night-compared to the countryside [2]. Therefore, including the anthropogenic heat, as a parameter in the simulations, is relevant for models prepared for the climate simulations [3,4].The urban microclimate is strongly connected to the anthropogenic heat released in the canyon. Cities with an efficient public transportation system and a central district cooling plant have a positive impact in improving the urban microclimate [5]. Annual average values show that cities such as Chicago (53 W/m 2 ), Montreal (99 W/m 2 ) and Budapest (43 W/m 2 ) have anthropogenic heat variation from 20 to 40 W/m 2 in summer, and from 70 to 210 W/m 2 in winter. The anthropogenic heat and the traffic schedule follow the same graphic distribution, having one peak in the morning and one peak in the evening [6].Abu Dhabi has developed rapidly over the past 60 years. During this time the urban settlement has grown from the main island towards the desert. The buildings located on the main ...

The rapid urbanization of the UAE, including medium sized cities like Al Ain City, has a significant relationship to local micro-climatic change. Al-Ain city in the southeast of the UAE and was originally an oasis. It has a hot and arid climate with a very dry and hot summer. The climate of the city is affected by the desert areas of red sand and the eastern Rocky Mountains. The local micro-climatic evolution can be studied and tracked using the local climate zone (LCZ) classification map. The districts of Al Ain are classified based on different factors, including surface cover and surface temperature, which were analysed using WUDAPT (World Urban Database and Access Portal Tools) software. The LCZ map is based on highresolution satellite images, which were used to classify regions based on building morphology and district pattern. The LCZ map results were compared with CFD (computational fluid dynamic) models that were simulated using ENVI-met software tool. The CFD models were optimized and validated based on on-site surveys and information taken from the local authorities, while the boundary conditions were validated using site measurements. Both models were analysed over the spring and summer seasons. Based on the results provided from WUDAPT and ENVI-met, a higher temperature was observed in the densest areas (downtown) and lower temperatures in the green zones (park, city date farms) and the result precision was higher in the colder season (autumn in this case).

As a result of an increasing demand for energy-efficient buildings with a better experience of user comfort, the built environment sector needs to consider the prediction of building energy performance, which during the design phase, is achieved when a building is handed over and used. There is, however, significant evidence that shows that buildings do not perform as anticipated. This discrepancy is commonly described as the ‘energy performance gap’. Building energy audit and post occupancy evaluation (POE) are among the most efficient processes to identify and reduce the energy performance gap and improve indoor environmental quality by observing, monitoring, and the documentation of in-use buildings’ operating performance. In this study, a case study of UAE university buildings’ energy audit, POE, and dynamic simulation were carried out to first, identify factors of the dynamic energy performance gap, and then to identify the utility of the strategy for reducing the gap. Furthermore, the building energy audit data and POE were applied in order to validate and calibrate a dynamic simulation model. This research demonstrated that the case study building’s systems were not operating as designed and almost a quarter of the cooling energy was wasted due to the fault of the building facility management of the mechanical systems. The more research findings were discussed in the paper.

Villas are a very common building typology in Abu Dhabi. Due to its preponderance in residential areas, studying how to effectively reduce energy demand for this type of building is critical for Abu Dhabi, and many similar cities in the region. This study aims to show the impact of proposed energy efficiency measures on a villa using a calibrated model and to demonstrate that to be accurate, the model must be driven using urban weather data instead of rural weather data due to the significance of the urban heat island effect. Available data for this case study includes construction properties, on-site (urban) weather data, occupancy-related loads and schedules and rural weather data. Four main steps were followed, weather data customisation combining urban and rural weather variables, model calibration using a genetic algorithm-based tool and simulating retrofit strategies. We created a calibrated model for electricity demand during 2016–2017 with a 4% normalized mean bias error and an 11% coefficient of variation of the mean square error. Changing from none to all retrofit strategies results in a 34% reduction in annual energy consumption. According to the calibrated model, increased urban temperatures cause a 7.1% increase in total energy consumption.

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The building industry is in constant change and the United Arab Emirates (UAE) is a leader in innovative solutions for green buildings. The standards used in achieving sustainable buildings, such as LEED, Estidama, have contributed to building structures that reduce energy consumption. More than 40% of the total energy is consumed by residential and commercial buildings as electricity. The strategies applied in a building in order to have low energy consumption vary depending on the region and climate. In the UAE, a country with a hot arid climate, these strategies have relevant importance. The aim of this study is to design an innovative parametric/dynamic façade in a new building, to be built on the United Arab Emirates University Campus, AL Ain, Abu Dhabi, UAE. The new structure is an additional library building (with additional functions to the current building). The design shall be based on the region’s architectural heritage. The modelling and simulation tools used are Rhino and plug-ins like Grasshopper. Furthermore, an optimization process of the parametric/dynamic façade is conducted. Based on the energy simulation results, the application of the innovative parametric/dynamic façade brings a reduction of 25% in the energy consumption of the building. In addition, the daylight improvement by the application of this façade is 44%. This research brings innovation in terms of the advanced tools used in calculating several parameters for the advanced façade and the process from concept to modeling and simulation. These findings are promising for regional industry due to the advanced tools and methods used. Moreover, it shall help the local authorities such as Abu Dhabi Municipality achieve the sustainability goals 2030.

In many cities that have experienced rapid growth like Abu Dhabi, urban microclimate scenarios evolve rapidly as well and it is important to study the urban thermal dynamics continuously. The Local Climate Zone (LCZ) classification considers factors related to the physical properties like surface cover and surface structure of the city which allow to analyze urban heat flows. Abu Dhabi city is rapidly expanding and is characterized by highly heterogeneous types of built forms that comprise mainly of old mid-rise and modern high-rise buildings with varied degrees of vegetation cover in different parts of the city. The fact that it is a coastal city in a desert environment makes it quite unique. This paper presents an approach of studying urban heat flows in such heterogeneous setup. First, the city is classified into local climate zones using images acquired by Landsat Satellite. Numerical simulations are performed in the designated LCZs using a computational fluid dynamics software, Envi-met. The results of Envi-met are calibrated and validated using in-situ measurements across all four seasons. The calibrated models are then applied to study entire Abu Dhabi island across different seasons. The results indicate a clear presence of urban heat island (UHI) effect when averaged over the full day which is varying in different zones. The zones with high vegetation do not show large average UHI effect whereas the effect is significant in densely built zones. The study also validates previous observations on the inversion of UHI effect during the day and in terms of diurnal response.

The city of Al Ain (Abu Dhabi, UAE) has a significant amount of mixed-use mid-rise buildings, especially in the city's central district. Because of the harsh arid climate of Al Ain, many of these buildings have high energy demands to accommodate the cooling load. By taking inspiration from the traditional Islamic architectural element, Mashrabiya, this study is concerned with exploring and identifying various, optimal Islamic geometric pattern (IGP) configurations used in cladding systems, with respect to energy consumption, daylighting, and quality views. The main objective of this study is to formulate a repertoire of IGPs that can be used in façade cladding systems that achieve significant reductions in energy consumption, while also providing sufficient daylighting and quality views. After a comprehensive literature review and local climate analysis, ten commonly-used IGPs will be modelled using the parametric software language Grasshopper and applied to the selected building modelled in Rhinoceros 3D, a 3D modelling program. Next, energy, daylight, and view quality simulations will be conducted using different orientations and during different seasons. The modelling process and simulations, along with the obtained results should give stakeholders a catalogue of optimal IGPs to refer to when selecting a passive exterior perforated cladding system. The study should also add to the knowledge of employing vernacular patterns to façade cladding systems in the hopes of strengthening the link to local culture.